Method of applying clay to jiggering molds



Nov. 16, 1943. w. J. MILLER 2,334,640

METHOD OF APPLYING CLAY TO JI GGERING MOLDS Original Filed July 20, v19555 INVENTOR I WILL 1AM JM/LLER article undergoing placement adjacent a dryer.

Patented Nov. 16, 1943 METHOD or APPLYING CLAYVTO JIGGERING MOLDS William J. Miller, Swissvale, Pa.

Original application July 20, 1935, Serial No. 32,391. Divided and this application March 18, 1940, Serial No. 324,468

14 Claims. (01. 25-456 This invention relates to a method of the manufacture of pottery ware, such as cups, saucers and the like known in the art as dinnerware from plasticadhesive clay as used in manualjiggering. It has to do with new and improved methods of ware production.

This application is a division of my co-pending application for United States Letters Patent, Serial No. 32,391 filed July 20, 1935 and relates particularly to the method of forming and applying clay charges to jiggering moldsr I The objects are to provide new and improved automatic ware fabricating methods and means which will displace the batter-out in the normal jigger crew; to automatically form and apply charges to molds; to manufacture superior'quality ware free from dirt, specks and drying in the display surfaces thereof.

In'the drawing, Fig. 1 is a top plan view of a fabricating machine for practicing my method.

Fig. 2 isa side elevation of the machine shown in Fig. 1. V

Fig. 8 is a detail view showing how charges of cracks clay are segregated and disposed on molds, and

Fig. 4 shows a hollow ware press.

According to the general system of my application supra, ware is fabricated progressively in or on absorbent molds, the operations of forming and feeding charges, spreading the charge over the mold surface; adhesively bonding the clay to the mold, jiggering and trimming all performed mechanically on automatic machinery. The molds are preferably transported manually from a dryer and placed on a conveyor from which each is subsequently removed and automatically fed first to the charge applying means and'thereafter to a succession of fabricating stations for procedural steps leading to the completion of the production after which it is removed to a dryer.

erally, a frame I having a three-point support on Wheels 2,'to avoid torsional stresses, one of which at 3 is swivelled to facilitate directional travel and ports drive motor I, apair of elongated mold conveyors A and B respectively; a charge forming and feeding means C; a mold transfer D for automatically feeding empty molds from conveyor A to position F for charging; another transfer E progresses charged molds to and through the die forming station G; profiling and trimming station .H and onto conveyor B, both of said transfers operating in timed relation with each other "and with. conveyors A and B the apparatus also The frame sup- 1 .40 The preferred apparatus, Fig. 1, comprises gengether. He then loads and 45a forelevatin'g the molds to'operating p0- sition. The machine operates in'repeated cycles and upon completion of each cycle'a finished piece of ware in or on its mold is transferred to'con veycr B, the molds accumulating thereon against the time when the operator will removethe same to the dryer. i j Normally, the operator places a billet of clay S on feeder belt 9 and manually advances it to correct cutting position and then loads the belt to capacity with reserve billets, welding the ends toempty molds on conveyor A to capacity andclutches in the drivethrough lever 31) and clutch 3a, whereupon empty molds are automatically transferred inconsecutive order to and through stations F, G and H, the operator continuing 'to place empty molds onconveyorjA until filled molds appear on conveyor B,

in sufficient numbers to; require, in the 'operators automatically transfer a mold from conveyor A'to centered position over ring chuck 8. The chuck is then elevated through double cam 46, crosshead 46a, and engages the mold'through the open bottom of frame 4, elevating it'to chargingpositicn adjacent the leadend of feederb'elt' 9 (see dotted lines, Fig. 2) whilst frame 4 is returned to its initial position.

The preferred billet form is that of a relatively large diameter elongate cylinder having mitered ends which represents a maximum volume "for a minimum peripheral surface area; By severing slices from the lead end of the slug, a disc-like charge is produced, having a maximum area of clean clay anda minimum exposed area (in the periphery) of contamination. j This contamination is principally in the form of microscopic iron particles that are detached from the surfaces of the knives, screw and Dug nozzle by the highly abrasiveacti'on of the clay and are normallydeposited'in the billet skin; If this skin'is laid against the mold face or ,if the clayis masticated during charge formation, teredjthroughout the ware and upon firing become visible as oil color specks in the display surfaces. My improved method confines contamination to the warefbrim'zone, generallyremoved by the trimmer-or at least covered by'dec- ,orations. o

the particles are scat- A clay slice of measured thickness is severed on the bias in overbalanced position by adjustable cutting wire l2 (see Fig. 3) which may be heated, dried or wiped of adhering clay to remove accumulation, to reduce its out sealing characteristics and insure free drop of the slice. The wire is preferably oscillated in a predetermined substantially rectilinear path by frame [3 having a shifting pivot in elongated bearings I200 attached to feeder frame [4, and connected to an actuat l ing crank l6, Fig. 2, by elastic members [8. Y

s of increased efficiency both as regards capillarity This crank is operated in unison with crosshead 48a, the position and extent of reciprocation being determined by the adjustment of nuts [5 on connecting rod H. b

- By severing charges on the center of acrowned roller 2| in overbalanced position'directly against the belt (Fig. 3), the slice may be guided direct 1y onto the mold according to the dotted line disclosure of Fig. 3 with the farther rim portion of. the slice face first engaging the mold.

After the mold is charged at F and lowered onto the end seat'42'of transfer E, the trans- 'fer is'shifted to right, Figs. 1 and 2, by levers 43,

and cam 44 on the shaft Gto advance the m old to the blank forming station G. The transfer may be'quickly adjusted to accommodate molds of other size by removing the dowelled bars 42a and substituting bars having mold seat portions of correct size. Chuck 45 on stand45a is then elevated by peak cams iiiand crossheatl 46a, lifting the mold into cooperation with a' stationary non-adhesive die 41, which engages, progres'sively spreads and: a'dhesively bonds the clay to the mold. v The chargefpreferably is in the form 0 of a disc and lies in centered orapproximately centered position on the mold covering only a portion of" the ware forming surface; upon en v i eme'nt with the die, the material is spread radially and evenly until the ware surface is completely covered, the contaminated slice 'brirn flowing to the mold brim and subsequently being trimmed or cracking off during drying. 7 g I After. the clay is applied to the mold and adhesively bonded thereto, the mold is advanced by transfer E to the profile station Hywhere it is rotated through belt and pulley l3 and 1 3 in engagement with the tool. 58 whilst fluid is applied, therebyremoving excess material from and smoothing 'andfinishing the surface of the clay,

whilst the mold is rotated, fa trimming tooled "trims the brim and upon termination of .the profiling'operation the mold is returnedto'conveyor E which shifts to the right and loads the mold onto conveyor 13, operating in timedrelation withconveyorA. The moldsare subsequentlytransferred to a dryer, all substantially as described'more' in "detail in my co-pending application supra.

The charge preferably is in the formof a disc and lies in centered'or approXimately'bentered position on the mold covering only'a portion of the ware formings'urface; upon engagement with the die, the material is spread radially and evenlyuntilthe ware surface is completely covered, the contaminated slice brimfiowingt'o'the cracking'offduring drying.

As distinguished over manuaLwherein' the clay mold brimfand subsequently being trimmedor.

is first batted out? into. a pancake oversize asto the diameter andthickness of thecompleted ware, independently of the niold'on which it isformed and then'appliedfthereto; the clay charge'isde posited directly onthemfold as it is severed. from spreading and applying the clay over the exposed surface of the mold provides a mechanical bond and resistance to dlslodgement under the higher speeds of mold rotation common to automatic equipment of this type.

Inmaking hollow ware such as cups and the like, the molds which are cavitous, as shown at M, in Fig. 4, are brought to the feeding position and there charged with clay in the manner aforesaid and are then transported to the press position where the clay charge is engaged by nonadhesive contour pl'ess member 9? upon elevation of the chuck 45a on pedestal 5. The die is supported n the lintel 41a of the machine in place of the flat ware die shown in Fig. 1. It has a threaded mounting stem on which is mounted a hand wheel 4-?0 by means of which it is attached to the lintel. :23 indicates the conduit by means of which steam is piped to the hollow interior.

'The clay charge which occupies a position preferably in the center of the bottom of the mold cavity is spread up the cavity wall incident to pressing, the clay flowing' vertically and to a certainjextent radially by virtue of the inclination of the cavity wall. i

Having thus described my invention, what I claim is:

1. A method of applying clay to the molding surface of pottery jigger'molds, whichcomprises, advancing a cylindrical body of clay containing material for several mold charges downwardly toward a cutting on position, slicing charges of clay from the leading end of the body and by gravity, depositing the slices as they are cut off, on the molding surface of successively presented molds in substantially centered position and then thereof said'charges beingof disc-like proportions and smaller diameter thanthe molding surfac of the mold but containing ample -material for the formation of the ware pieceedropping the charge by gravity incident to segregation on substantially thecenter of distribution of the mold,

the parent massand' is therispr'ead'ondiffulsed over the ware forming surface of the mold (by a pressing the charg betw een'themold and nonrotatable preforming die thereby spreading out the charge radially jandbrimwise to cover exposed portions of the molding surface and adliesivelybond the charge thereto'l l 3. The method of, feeding andapplying clayto absorbent iig ering molds in the manufactured pottery ware which comprises, providing a substantially cylindrical body of clay containing within the mass thereof "a multiple of mold charges the cross sectional dimension thereof-belng smaller'thanthe diameter ofthe molding surface of the m'o id slicing'the aforesaid mass "across the'long "axis thereof inorder to produce a substantially disc-like body having substantially flat top and bottom surfaces, depositing the aforesaid charge incident to thesegre'gation thereof from the parent mass on the molding surface of the mold, said charge being locatedin substantially thecenter of distribution thereof but covering only a portion of said molding surface and then pressing the aforesaid charge between the mold and a matrix to spread the clay radially over exposed portions of the mold.

gered pottery ware which comprises, providing a solid column of clay containing a multiple of mold charges, advancingthe aforesaid body in the direction of the long axis thereof toward a point of charge segregation and there slicing charges of clay from the aforesaid mass by cutting crosswise of the long axis, said charge thus produced being of disc-like proportions and having substantially "flat top and bottom surfaces with the material therein uniformly distributed from the center to the brim, depositing said charge on substantially the center of distribution of the mold incident to segregation, said mold being positioned so as to receive said charge upon segregation and thereafter pressing the charge of clay between the mold and a preforming die to spread out the clay brimwise in all directions substantially simultaneous to cover the exposed portions of the molding surface. g I g 5. The method of feeding and applying clay to absorbent jiggering molds in the manufacture of jig-gered pottery ware which comprises, providing a cylindrical body of clay containing a multiple of mold charges, slicing the body crosswise of the long axis thereof to produce a mold charge of substantially disc-like proportions having substantially flat top and bottom surfaces,

depositing the aforesaid charge on one of these surfaces on the mold, said charge being of less diameter than that of the molding surface and thereafter pressing the charge between a mold and a non-adhesive matrix to reduce the body in thickness and cause it to spread over the exposed portions of the molding surface said clay flowing radially and brimwise under the pressure. exerted.

6. The method of feeding and applying plastic clay to absorbent ji-ggering molds in the manufacture of jiggered fiat ware which comprises, providing in registry with a superimposed body of clay a mold, the molding surface of which is positioned so as to receive a body of clay segregated from said superimposed mass, slicing said mass across the long axis thereof to thereby produce a charge of clay of substantially disc-like proportions of less diameter than the molding surface of the mold, depositing said slice on the center of distribution of the mold, the material in said charge being uniformly distributed from the axial center thereof to the periphery and thereafter pressing the charge between the mold and a non-adhesive matrix to flow the clay radially over the exposed portion of the molding surface and adhesively bond the clay thereto.

- 4. The method of feeding and applying clay to plaster jiggering molds in the manufacture of jig-' cession clay charges of uniform shape,lbulk-a'nd thickness, said charges being of less diameter than the molding surface of the molds and having the material therein uniformly. distributed from the center toward the perimeterQpressing the charges of clay between the aforesaid molds and anon-adhesive die having a pressing surand smaller diameter'than the molding surface of the mold but containing ample materialfor the formation of the ware piece, depositing-the charge concurrently with segregation on substantially the center'of distribution of the mold, pressing the charge between the mold and a non-rotatable non-adhesive contoured matrix thereby spreading the charge radially'and brimwise to cover the exposed portion of the molding surface and adhesively bond the charge thereto. 9. The method of feeding and applying clay to absorbent jiggering molds in. the manufacture 'of jiggered flat ware which comprises, providing a substantially cylindrical body of clay containing ,a multiple of mold charges, segregating charges of clay therefrom by slicing the aforesaid cylindrical mass across the long axis thereof said slice being disc-like in shape and of substantially uniform thickness overall, initiating the progress of the slice toward the mold whilst partly attached to the parent body and applying the zone initially detached to the mold first, the remainder progressively dropping into place to thereby expel air between the charge and mold,

the bulk of the charge being located'within a zone less than the entire area of the molding surface and thereafter pressing the charge of clay between the mold and'a non-adhesive matric to thereby flow the clay radially in contact with the molding surface to cover the theretofore exposed areas of the molding surface.

7. The method of feeding and applying plastic relation with the presentation of moldsat the charging position, slicing the superimposed body across the long axis thereof to produce'in suc- 10. In the manufacture of pottery ware, the method of applying a charge of clay to an absorbent jiggering mold which comprises, projecting a mass of clay of cylindrical proportions downwardly toward a mold the lead endof themass being smaller in diameter than the diameter of the molding surface, slicing the mass crosswise of the long axis at the leading endito produce a charge of clay of circular proportions substantially uniform in thickness, commencing the out at the periphery and continuing the out toward the opposite side, the zone initially severed parting from the mass and falling toward the V mold and engaging the molding surface in advance of the re'mainder'of the slice to preclude air entrapment, centering the'slice of clay on substantially the center of distribution of the mold by'locating the mold in proper position as respects the line of fall of the slice and thereafter pressing the slice between the mold and a, nonadhesive matrix to expand the clay radially over the exposed surface of the mold.

11. The method of feeding and applying plastic clay to jiggering molds in the manufacture of jiggered pottery ware which comprises, transporting jiggering molds in succession into regclay and concurrent with the presentation of molds at such position, slicing the end'of the superimposed body to produce in succession clay charges of uniform shape; bulk and thickness, permitting such charges tolgravitate directly onto 7 the molding surface of themold within the interval such mold is in registry with said superimposed mass of clay, transportirigflthe charged molds in succession to a preforming position and there spreading out the clay with a die having a spreading surface complementary to thegmolding surface.

12. A method of applying clay to jiggering molds in the manufacture of dinnerware, which comprises slicing from a; cylindrical 1 extruded mass of plastic clay, in a plane transverse to its longitudinal axis, a sequenceof substantially circular mold charges of uniform thickness and of materially less diameter than the molding surfaces of the molds upon which they are to be fabricated, said charges each containing sufficient material for the fabrication of the ware in question, depositing the charges onto the centers of the molding surfaces of the molds, and thereafter by. the application of uniform pressure spreading out the clay of the charges evenly in all radial directions to cover the molding surfaces and bond the clay to the molds.

13. The method of preparing clay charges on plaster jiggering molds for the purpose of mak- 'ing dinnerware which comprises the steps of extruding a mass of plastic clay of cylindrical cross section and of smaller diameter than the molding surface, slicing a sequence of mold charges of a material thickness from the end of the mass, dropping the charges by gravity with a flat side centered on the molding surface, and thereafter pressing the charge in a direction normal to its flat surface to spread the clay uniformly in all radial directions over the molding surface, thereby reducing the thickness of the charge to preshape it on the mold and bond it to the plaster mold surface.

14.,A method of applying clay to J'iggerins' molds in the manufacture of dinnerware, which comprises slicing from an extruded mass of plastic clay, having a cross sectional area symmetrical to that of the molding surface of the molds but of less area than the latter, in a plane transverse to its longitudinal axis, a sequence of mold charges of uniform thickness, said charges each containing sufficient material for the fabrication of the Ware in question, dropping the charges by ravity onto the molding surfaces of the molds, so that they are symmetrical thereto, and thereafter by the application of uniform pressure spreading the clay of the charges evenly in all radial directions to cover the molding surfaces and bond the clay to the molds.

WILLIAM J. MILLER. 

